Apparatus and method for refining metal

Abstract

A metal-refining converter comprises an elongated vessel for containing a melt to be refined and which tilts so that it can be positioned upright or horizontal. This vessel has an upper end having a charging opening provided with a removable gas-tight cover and a lower end provided with a channel-type inductor, and the vessel has a closable tap hole in its side which is downward when the vessel is horizontal. The vessel is charged with the melt to be refined, via its charging opening. With the vessel upright, the vessel is provided with means for injecting refining material into the melt while it is heated by the inductor. After the refining period, the vessel is tilted to its horizontal position, the vessel having an internal contour such that a space is formed over the melt, the gas-tight cover being applied at that time. Non-oxidizing gas is injected into the vessel and with the inductor continuing to heat the melt, the latter is tapped via the tap hole. Control of the gas pressure within the vessel and of the electric power applied to the inductor, permits tapping to be effected, for example, via bottom pouring into ingot molds, at a constant rate and temperature. With these two normally varying factors under complete control, high-quality castings are obtained.